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1.
Opt Lett ; 49(15): 4182-4185, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090889

RESUMEN

Replica symmetry breaking (RSB) has been introduced in a random laser to investigate the interactions between disorder and fluctuations. In this work, the dynamic difference between four non-energy transfer and Förster resonance energy transfer (FRET)-assisted random laser systems is investigated based on RSB. It is found that FRET is one of the key factors influencing RSB, and it is demonstrated that RSB in a random laser is not robust. This dynamic difference can be attributed to the different disorders induced by the gain mechanism in different random laser systems. This provides experimental evidence and theoretical support for the classification feasibility of RL with different emission mechanisms employing RSB.

2.
JMIR Public Health Surveill ; 10: e55822, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39140274

RESUMEN

Background: Studies have reported the adverse effects of cold events on influenza. However, the role of critical factors, such as characteristics of cold spells, and regional variations remain unresolved. Objective: We aimed to systematically evaluate the association between cold spells and influenza incidence in mainland China. Methods: This time series analysis used surveillance data of daily influenza from 325 sites in China in the 2014-2019 period. A total of 15 definitions of cold spells were adopted based on combinations of temperature thresholds and days of duration. A distributed lag linear model was used to estimate the short-term effects of cold spells on influenza incidence during the cool seasons (November to March), and we further explored the potential impact of cold spell characteristics (ie, intensity, duration, and timing during the season) on the estimated associations. Meta-regressions were used to evaluate the modification effect of city-level socioeconomic indicators. Results: The overall effect of cold spells on influenza incidence increased with the temperature threshold used to define cold spells, whereas the added effects were generally small and not statistically significant. The relative risk of influenza-associated with cold spells was 3.35 (95% CI 2.89-3.88), and the estimated effects were stronger during the middle period of cool seasons. The health effects of cold spells varied geographically and residents in Jiangnan region were vulnerable groups (relative risk 7.36, 95% CI 5.44-9.95). The overall effects of cold spells were positively correlated with the urban population density, population size, gross domestic product per capita, and urbanization rate, indicating a sterner response to cold spells in metropolises. Conclusions: Cold spells create a substantial health burden on seasonal influenza in China. Findings on regional and socioeconomic differences in the health effects of cold spells on seasonal influenza may be useful in formulating region-specific public health policies to address the hazardous effects of cold spells.


Asunto(s)
Frío , Gripe Humana , Humanos , China/epidemiología , Gripe Humana/epidemiología , Frío/efectos adversos , Incidencia , Estaciones del Año
3.
J Am Chem Soc ; 146(28): 18892-18898, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38968086

RESUMEN

Herein, we designed a reaction for the desymmetrization-addition of cyclopropenes to imines by leveraging the synergy between photoredox and asymmetric cobalt catalysis. This protocol facilitated the synthesis of a series of chiral functionalized cyclopropanes with high yield, enantioselectivity, and diastereoselectivity (44 examples, up to 93% yield and >99% ee). A possible reaction mechanism involving cyclopropene desymmetrization by Co-H species and imine addition by Co-alkyl species was proposed. This study provides a novel route to important chiral cyclopropanes and extends the frontier of asymmetric metallaphotoredox catalysis.

4.
New Phytol ; 243(5): 2021-2036, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39014531

RESUMEN

Phytohormones possess unique chemical structures, and their physiological effects are regulated through intricate interactions or crosstalk among multiple phytohormones. MALDI-MSI enables the simultaneous detection and imaging of multiple hormones. However, its application for tracing phytohormones is currently restricted by low abundance of hormone in plant and suboptimal matrix selection. 2,4-Dihydroxy-5-nitrobenzoic acid (DHNBA) was reported as a new MALDI matrix for the enhanced detection and imaging of multiple phytohormones in plant tissues. DHNBA demonstrates remarkable sensitivity improvement when compared to the commonly used matrix, 2,5-dihydroxybenzoic acid (DHB), in the detection of isoprenoid cytokinins (trans-zeatin (tZ), dihy-drozeatin (DHZ), meta-topolin (mT), and N6-(Δ2-isopentenyl) adenine (iP)), jasmonic acid (JA), abscisic acid (ABA), and 1-aminocyclo-propane-1-carboxylic acid (ACC) standards. The distinctive properties of DHNBA (i.e. robust UV absorption, uniform matrix deposition, negligible background interference, and high ionization efficiency of phytohormones) make it as an ideal matrix for enhanced detection and imaging of phytohormones, including tZ, DHZ, ABA, indole-3-acetic acid (IAA), and ACC, by MALDI-MSI in various plant tissues, for example germinating seeds, primary/lateral roots, and nodules. Employing DHNBA significantly enhances our capability to concurrently track complex phytohormone biosynthesis pathways while providing precise differentiation of the specific roles played by individual phytohormones within the same category. This will propel forward the comprehensive exploration of phytohormonal functions in plant science.


Asunto(s)
Reguladores del Crecimiento de las Plantas , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Reguladores del Crecimiento de las Plantas/metabolismo , Reguladores del Crecimiento de las Plantas/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Gentisatos/metabolismo , Gentisatos/química
5.
J Chromatogr A ; 1731: 465180, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39053255

RESUMEN

Novel magnetic covalent organic frameworks (COFs) were prepared by one-pot synthetic strategy and employed as an efficient adsorbent for magnetic solid-phase extraction (MSPE) of naphthaleneacetic acid (NAA) in food samples. Depending on the predesigned the hydrogen bonding, π-π and hydrophobic interactions of magnetic COFs, the efficient and selective extraction process for NAA was achieved within 15 min. The magnetic COFs adsorbent combined with HPLC-UV was devoted to develop a novel quantitative method for NAA in complex food. The method afforded good coefficient in range of 0.002-10.0 µg mL-1 and low limit of detection was 0.0006 µg mL-1. And the newly established method afforded less adsorbent consumption, wider linearity and lower LODs than the reported analytical methods. Ultimately, the method was successfully applied to determine NAA in fresh pear, tomato and peach juice. The magnetic COFs based MSPE coupled with HPLC-UV method provided a simple, efficient and dependable alternative to monitor trace NAA in food samples.


Asunto(s)
Límite de Detección , Estructuras Metalorgánicas , Ácidos Naftalenoacéticos , Extracción en Fase Sólida , Extracción en Fase Sólida/métodos , Cromatografía Líquida de Alta Presión/métodos , Ácidos Naftalenoacéticos/análisis , Ácidos Naftalenoacéticos/química , Estructuras Metalorgánicas/química , Adsorción , Contaminación de Alimentos/análisis , Solanum lycopersicum/química , Jugos de Frutas y Vegetales/análisis
6.
Mol Cell ; 84(15): 2984-3000.e8, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39002544

RESUMEN

5-methylcytosine (m5C) is a prevalent RNA modification crucial for gene expression regulation. However, accurate and sensitive m5C sites identification remains challenging due to severe RNA degradation and reduced sequence complexity during bisulfite sequencing (BS-seq). Here, we report m5C-TAC-seq, a bisulfite-free approach combining TET-assisted m5C-to-f5C oxidation with selective chemical labeling, therefore enabling direct base-resolution m5C detection through pre-enrichment and C-to-T transitions at m5C sites. With m5C-TAC-seq, we comprehensively profiled the m5C methylomes in human and mouse cells, identifying a substantially larger number of confident m5C sites. Through perturbing potential m5C methyltransferases, we deciphered the responsible enzymes for most m5C sites, including the characterization of NSUN5's involvement in mRNA m5C deposition. Additionally, we characterized m5C dynamics during mESC differentiation. Notably, the mild reaction conditions and preservation of nucleotide composition in m5C-TAC-seq allow m5C detection in chromatin-associated RNAs. The accurate and robust m5C-TAC-seq will advance research into m5C methylation functional investigation.


Asunto(s)
5-Metilcitosina , Sulfitos , Transcriptoma , 5-Metilcitosina/metabolismo , 5-Metilcitosina/química , Animales , Humanos , Ratones , Sulfitos/química , Metiltransferasas/metabolismo , Metiltransferasas/genética , Perfilación de la Expresión Génica/métodos , Diferenciación Celular
7.
Int J Womens Health ; 16: 1033-1040, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38835834

RESUMEN

Purpose: Female infertility is a global health concern. The aim of this study was to investigate the relationship between regulatory T (Treg) cells and helper T cells 17 (Th17) in peripheral blood and unexplained infertility (UI). In addition, we explored potential valuable diagnostic biomarkers for patients with UI and ascertained whether Treg and Th17 cells are associated with primary and secondary UI. Patients and Methods: The patients underwent standard fertility evaluation test, including blood tests, ultrasound examination, fallopian tube tests, ovulation assessment, and male partner's semen analysis. According to the inclusion and exclusion criteria, this study enrolled 37 patients with UI (30 with primary UI and 7 with secondary UI) and 26 age-matched healthy volunteers as the control group. Flow cytometry was used to detect the frequency of Treg and Th17 cells. The area under the receiver operating characteristic curve (AUC) with a 95% confidence interval (CI) was used to assess the diagnostic performance. An AUC > 0.800 indicated good diagnostic performance. Results: The percentage of Treg decreased significantly, whereas the percentage and absolute count of Th17 cells increased. Moreover, the Th17/Treg ratio in patients with UI increased significantly. As a diagnostic biomarker for UI, the Th17/Treg ratio exhibited remarkable diagnostic performance (AUC: 0.813 (95% CI = 0.709-0.917)). However, the percentages and absolute counts of Treg and Th17 cells in the peripheral blood of women with primary and secondary UI, as well as their Th17/Treg ratios, did not differ significantly. Conclusion: The distribution of Treg and Th17 cells is imbalanced in patients with UI. Therefore, the Th17/Treg ratio may be a promising indicator of UI. However, there were no significant differences in the distribution of Treg and Th17 cells between women with primary and secondary UI.

8.
Parasit Vectors ; 17(1): 250, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38849919

RESUMEN

BACKGROUND: Flea bites could trigger a series of complex molecular responses in the host. However, our understanding of the responses at the molecular level is still relatively limited. This study quantifies the changes in gene expression in mice after flea bites by RNA sequencing (RNA-seq) from their spleens, revealing the potential biological effects of host response to flea bites. METHODS: RNA-seq was used for transcriptome analysis to screen for differentially expressed genes (DEGs) between the control mice group and the flea bite mice group. Gene ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were performed on DEGs. Protein-protein interaction (PPI) network analysis on DEGs related to immune processes was performed. Finally, we randomly selected several genes from the screened DEGs to validate the results from the transcriptome data by real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR). RESULTS: A total of 521 DEGs were identified, including 277 upregulated and 244 downregulated. There were 258 GO terms significantly enriched by upregulated DEGs and 419 GO terms significantly enriched by downregulated DEGs. Among the upregulated DEGs, 22 GO terms were associated with immune cells (e.g., B cells and T cells) and immune regulatory processes, while among the downregulated DEGs, 58 GO terms were associated with immune cells and immune regulatory processes. Through PPI analysis, we found that CD40 molecules with significantly downregulated expression levels after flea bites may play an important role in host immune regulation. Through KEGG pathway enrichment analysis, a total of 26 significantly enriched KEGG pathways were identified. The RT-qPCR analysis results indicated that the transcriptome sequencing results were reliable. CONCLUSIONS: Through in-depth analysis of transcriptome changes in mice caused by flea bites, we revealed that flea bites could stimulate a series of biological and immunological responses in mice. These findings not only provided a deeper understanding of the impact of flea bites on the host but also provided a basis for further research on the interaction between ectoparasites and the host. We believe that digging deeper into the significance of these transcriptome changes will help reveal more about the adaptive response of the host to ectoparasites.


Asunto(s)
Perfilación de la Expresión Génica , Transcriptoma , Xenopsylla , Animales , Ratones , Xenopsylla/genética , Mordeduras y Picaduras de Insectos/inmunología , Ontología de Genes , Mapas de Interacción de Proteínas , Bazo/inmunología , Bazo/metabolismo , Femenino , Análisis de Secuencia de ARN
9.
Med Phys ; 2024 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-38734991

RESUMEN

BACKGROUND: In recent years, genetic algorithms have been applied in the field of nuclear technology design, producing superior optimization results compared to traditional methods. They can be employed in the design and optimization of beam shaping assemblies (BSA) BSA to obtain the desired neutron beams. But it should be noted that the direct combination of Monte Carlo methods with genetic algorithms requires a significant amount of computational resources and time. PURPOSE: Design and optimize BSA more efficiently to achieve neutron beams that meet specified recommendations. METHODS: We propose an approach of NSGA II with crucial variables which are identified by multivariate statistical techniques. This approach significantly reduces the problem sizes, thus reducing the time required for optimization. We illustrate this methodology using the example of BSA design for AB-BNCT. RESULTS: The computational efficiency has tripled with crucial variables. By using NSGA II, we obtained optimized models conforming to both the new and old version IAEA BNCT guidelines through a single optimization process and subjected them to phantom analysis. The results demonstrate that models obtained through this method can meet the IAEA recommendations with deep advantage depth (AD) and high absorbed ratio (AR). CONCLUSION: The genetic algorithm with crucial variables displays tremendous potential in addressing BSA optimization challenges.

10.
Heliyon ; 10(9): e30511, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38765139

RESUMEN

Objective: To prospectively determine the median effective dose (ED50) of propofol for inhibiting a response to laryngeal mask airway (LMA) insertion when combined with different doses of esketamine in female patients. Methods: A total of 58 female patients (aged 20-60 years, ASAⅠ-Ⅱ) scheduled for elective hysteroscopy were enrolled and randomly divided into 2 groups, one of which was administered 0.2 mg/kg of esketamine (K1 group, n = 28) and the other 0.3 mg/kg of esketamine (K2 group, n = 30). The 2 groups received the corresponding doses of esketamine intravenously, followed by an intravenous injection of propofol (injection time was 30 s). The initial dose of propofol was 2 mg/kg, and the dose ratio of propofol in the adjacent patients was 0.9. If a positive reaction occurred due to LMA insertion, the dose ratio in the next patient was increased by 1 gradient; if not, the dose ratio was decreased by 1 gradient. The ED50, 95 % effective dose (ED95) and 95 % confidence interval (CI) of propofol for inhibiting a response to LMA insertion in the 2 esketamine groups were calculated using probit analysis. Results: The ED50 of propofol for inhibiting a response to LMA insertion in female patients was 1.95 mg/kg (95 % CI, 1.82-2.08 mg/kg) in the K1 group and 1.60 mg/kg (95 % CI, 1.18-1.83 mg/kg) in the K2 group. The ED95 of propofol for inhibiting a response to LMA insertion in female patients was 2.22 mg/kg (95 % CI, 2.09-2.86 mg/kg) in the K1 group and 2.15 mg/kg (95 % CI, 1.88-3.09 mg/kg) in the K2 group. Conclusion: Propofol combined with 0.3 mg/kg of esketamine has low ED50 and ED95 effective doses for inhibiting an LMA insertion response in female patients undergoing hysteroscopy and surgery. There were no significant adverse effects, but the additional dose of propofol and airway pressure were significantly higher than those in the group administered 0.2 mg/kg of esketamine. Based on the results, we recommend the combination of propofol with 0.2 mg/kg esketamine for optimal conditions during LMA insertion in women undergoing hysteroscopy.

11.
Insects ; 15(5)2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38786894

RESUMEN

Despite being the most widespread blister beetle subfamily, Nemognathinae is unfairly understudied in China. In this study, a new genus and species, Sinostenoria yangi Pan, from northern China is described and illustrated. The antennae, elytra, hind wings, and claws of the new genus form a truly unique set of characteristics never observed in other genera of Nemognathini Laporte de Castelnau, 1840. Three species from China are newly recorded and illustrated: Megatrachelus sibiricus (Tauscher, 1812), Zonitomorpha dollei (Fairmaire 1889), and Stenodera djakonovi Aksentjev, 1978. The genus Oreomeloe Tan, 1981, is transferred from the tribe Meloini Gyllenhal, 1910, to Nemognathini based on an examination of the types. Aiming to test the morphology-based placement of the new genus, we conducted molecular phylogenetic analyses using two mitochondrial (COI, 16S) and three nuclear markers (28S, CAD, ITS2). The results confirm our tribal assignment of the new genus and support a clade that consists of Sinostenoriagen. n., Longizonitis Pan and Bologna, 2018, Stenoria cf. grandiceps, and Ctenopus cf. persicus.

12.
Sci Transl Med ; 16(747): eadl1408, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38748772

RESUMEN

Essential tremor (ET) is the most prevalent movement disorder, characterized primarily by action tremor, an involuntary rhythmic movement with a specific frequency. However, the neuronal mechanism underlying the coding of tremor frequency remains unexplored. Here, we used in vivo electrophysiology, optogenetics, and simultaneous motion tracking in the Grid2dupE3 mouse model to investigate whether and how neuronal activity in the olivocerebellum determines the frequency of essential tremor. We report that tremor frequency was encoded by the temporal coherence of population neuronal firing within the olivocerebellums of these mice, leading to frequency-dependent cerebellar oscillations and tremors. This mechanism was precise and generalizable, enabling us to use optogenetic stimulation of the deep cerebellar nuclei to induce frequency-specific tremors in wild-type mice or alter tremor frequencies in tremor mice. In patients with ET, we showed that deep brain stimulation of the thalamus suppressed tremor symptoms but did not eliminate cerebellar oscillations measured by electroencephalgraphy, indicating that tremor-related oscillations in the cerebellum do not require the reciprocal interactions with the thalamus. Frequency-disrupting transcranial alternating current stimulation of the cerebellum could suppress tremor amplitudes, confirming the frequency modulatory role of the cerebellum in patients with ET. These findings offer a neurodynamic basis for the frequency-dependent stimulation of the cerebellum to treat essential tremor.


Asunto(s)
Cerebelo , Temblor Esencial , Neuronas , Núcleo Olivar , Temblor Esencial/fisiopatología , Animales , Humanos , Núcleo Olivar/fisiopatología , Cerebelo/fisiopatología , Ratones , Masculino , Optogenética , Femenino , Estimulación Encefálica Profunda , Persona de Mediana Edad , Electroencefalografía , Anciano
13.
J Gen Virol ; 105(5)2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38767609

RESUMEN

Hepeviruses have been identified in a broad range of animal hosts, including mammals, birds, and fish. In this study, rodents (n=91) from seven different species and ten pikas (Ochotona curzoniae) were collected in Qinghai Province, China. Using transcriptomic sequencing and confirmatory molecular testing, hepeviruses were detected in 27 of 45 (60 %) long-tailed dwarf hamsters (Cricetulus longicaudatus) and were undetected in other rodents and pika. The complete genome sequences from 14 representative strains were subsequently obtained, and phylogenetic analyses suggested that they represent a novel species within the genus Rocahepevirus, which we tentatively designated as Cl-2018QH. The virus was successfully isolated in human hepatoma (Huh-7) and murine fibroblast (17 Cl-1) cell lines, though both exhibited limited replication as assayed by detection of negative-sense RNA intermediates. A129 immunodeficient mice were inoculated with Cl-2018QH and the virus was consistently detected in multiple organs, despite relatively low viral loads. In summary, this study has described a novel rodent hepevirus, which enhances our knowledge of the genetic diversity of rodent hepeviruses and highlights its potential for cross-species transmission.


Asunto(s)
Genoma Viral , Hepevirus , Filogenia , Animales , China , Cricetinae , Ratones , Hepevirus/genética , Hepevirus/aislamiento & purificación , Hepevirus/clasificación , Humanos , Línea Celular , ARN Viral/genética
14.
Risk Manag Healthc Policy ; 17: 1349-1359, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38803623

RESUMEN

Objective: This study aimed to clarify the association between suboptimal health status and health-related productivity loss among primary healthcare workers in China. Material and Methods: A field questionnaire survey was conducted with a multistage sampling among primary healthcare workers. The data on sub-health and health-related productivity loss were collected using the Sub-health Measurement Scale Version 1.0 and Work Productivity and Activity Impairment Questionnaire: General Health, respectively. Ordinary least squares regression was used to evaluate the association of the suboptimal health and health-related productivity loss. Subgroup analyses were performed by occupation (physician and nurse). Results: Front-line primary healthcare workers (N = 1709) from 31 provinces in China responded to the survey. Of all participants, 73.43% experienced suboptimal health. The status of being in physical suboptimal health (Coef. = 0.050, p < 0.001, 95% CI = [0.031,0.070]) and mental suboptimal health (Coef. = 0.040, p < 0.001, 95% CI = [0.020,0.059]) status exerted significant effect on the extent of health-related productivity loss among primary healthcare workers in China. Nurses in social adaptation suboptimal health status (Coef. = 0.030, p = 0.027, 95% CI = [0.003,0.057]) had significant effect on health-related productivity loss. Conclusion: The prevalence of suboptimal health is high among the respondents. Providing support for primary healthcare workers from bio-psycho-social aspects is an effective measure to promote their occupational health and improve their productivity.

15.
ACS Nano ; 18(23): 15204-15217, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38803167

RESUMEN

The Pseudomonas aeruginosa biofilm in recalcitrant chronic lung infections not only develops high antimicrobial tolerance but also induces an aberrant host inflammatory response. The metabolic condition plays a vital role in both the antimicrobial susceptibility of bacteria and the inflammatory response of immune cells, thereby offering a potential therapeutic target. Herein, we described a metabolic modulation strategy by using ultrasound-responsive liposomal nanoparticles containing a sonosensitizer and a hypoxia-activated prodrug against biofilm-associated chronic lung infections. Under ultrasound stimulation, the sonosensitizer generates antibacterial reactive oxygen species by oxygen consumption. Subsequently, the oxygen consumption-mediated hypoxia not only induces the anaerobic metabolism of bacteria for antibiotic activation but also triggers the glycolysis pathway of immune cells for inflammatory activation. Such metabolic modulation strategy demonstrated efficient therapeutic efficacy for P. aeruginosa biofilm-induced chronic lung infections in mice models and provides a promising way for combating biofilm-associated chronic infections.


Asunto(s)
Antibacterianos , Biopelículas , Infecciones por Pseudomonas , Pseudomonas aeruginosa , Animales , Antibacterianos/farmacología , Antibacterianos/química , Pseudomonas aeruginosa/efectos de los fármacos , Ratones , Biopelículas/efectos de los fármacos , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/inmunología , Nanopartículas/química , Liposomas/química , Enfermedad Crónica , Especies Reactivas de Oxígeno/metabolismo , Profármacos/farmacología , Profármacos/química
16.
BMC Genomics ; 25(1): 262, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38459433

RESUMEN

Plague, as an ancient zoonotic disease caused by Yersinia pestis, has brought great disasters. The natural plague focus of Marmota himalayana in the Qinghai-Tibet Plateau is the largest, which has been constantly active and the leading source of human plague in China for decades. Understanding the population genetics of M. himalayana and relating that information to the biogeographic distribution of Yersinia pestis and plague outbreaks are greatly beneficial for the knowledge of plague spillover and arecrucial for pandemic prevention. In the present research, we assessed the population genetics of M. himalayana. We carried out a comparative study of plague outbreaks and the population genetics of M. himalayana on the Qinghai-Tibet Plateau. We found that M. himalayana populations are divided into two main clusters located in the south and north of the Qinghai-Tibet Plateau. Fourteen DFR genomovars of Y. pestis were found and exhibited a significant region-specific distribution. Additionally, the increased genetic diversity of plague hosts is positively associated with human plague outbreaks. This insight gained can improve our understanding of biodiversity for pathogen spillover and provide municipally directed targets for One Health surveillance development, which will be an informative next step toward increased monitoring of M. himalayana dynamics.


Asunto(s)
Marmota , Yersinia pestis , Animales , Humanos , Tibet/epidemiología , China/epidemiología , Brotes de Enfermedades , Yersinia pestis/genética , Variación Genética
17.
Opt Lett ; 49(5): 1357-1360, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38427012

RESUMEN

Flexible engineering of the complex shapes of the surface nanoscale axial photonics (SNAP) bottle microresonators (SBMs) is challenging for future nanophotonic technology applications. Here, we experimentally propose a powerful approach for the one-step fabrication of SBMs with simultaneous negative and positive radius variations, exhibiting a distinctive "bump-well-bump" profile. It is executed by utilizing two focused and symmetrical CO2 laser beams exposed on the fiber surface for only several hundred milliseconds. The spectral characteristics of different eigenmodes are analyzed, providing deep insights into the complex physical processes during the CO2 laser exposure. The shapes of the SBMs can be flexibly adjusted by the exposure time, laser power, and applied pre-strains. As a proof of this technique, the developed approach enables the efficient production of a bat SBM, ensuring a uniform field amplitude of the bat mode over the length exceeding 120 µm with 7% deviation. Our proposed technique provides a powerful technique for the efficient fabrication of SBMs with predetermined shapes, laying the groundwork for its applications on microscale optical signal processing, quantum computing, and so on.

18.
Huan Jing Ke Xue ; 45(2): 1080-1089, 2024 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-38471945

RESUMEN

Tetrachloroethylene (PCE) and trichloroethylene (TCE) are typical volatile halogenated organic compounds in groundwater that pose serious threats to the ecological environment and human health. To obtain an anaerobic microbial consortium capable of efficiently dechlorinating PCE and TCE to a non-toxic end product and to explore its potential in treating contaminated groundwater, an anaerobic microbial consortium W-1 that completely dechlorinated PCE and TCE to ethylene was obtained by repeatedly feeding PCE or TCE into the contaminated groundwater collected from an industrial site. The dechlorination rates of PCE and TCE were (120.1 ±4.9) µmol·ï¼ˆL·d)-1 and (172.4 ±21.8) µmol·ï¼ˆL·d)-1 in W-1, respectively. 16S rRNA gene amplicon sequencing and quantitative PCR (qPCR) showed that the relative abundance of Dehalobacter increased from 1.9% to 57.1%, with the gene copy number increasing by 1.7×107 copies per 1 µmol Cl- released when 98.3 µmol of PCE was dechlorinated to cis-1,2-dichloroethylene (cis-1,2-DCE). The relative abundance of Dehalococcoides increased from 1.1% to 53.8% when cis-1,2-DCE was reductively dechlorinated to ethylene. The growth yield of Dehalococcoides gene copy number increased by 1.7×108 copies per 1 µmol Cl- released for the complete reductive dechlorination of PCE to ethylene. The results indicated that Dehalobacter and Dehalococcoides cooperated to completely detoxify PCE. When TCE was used as the only electron acceptor, the relative abundance of Dehalococcoides increased from (29.1 ±2.4)% to (7.7 ±0.2)%, and gene copy number increased by (1.9 ±0.4)×108 copies per 1 µmol Cl- released, after dechlorinating 222.8 µmol of TCE to ethylene. The 16S rRNA gene sequence of Dehalococcoides LWT1, the main functional dehalogenating bacterium in enrichment culture W-1, was obtained using PCR and Sanger sequencing, and it showed 100% similarity with the 16S rRNA gene sequence of D. mccartyi strain 195. The anaerobic microbial consortium W-1 was also bioaugmented into the groundwater contaminated by TCE at a concentration of 418.7 µmol·L-1. The results showed that (69.2 ±9.8)% of TCE could be completely detoxified to ethylene within 28 days with a dechlorination rate of (10.3 ±1.5) µmol·ï¼ˆL·d)-1. This study can provide the microbial resource and theoretical guidance for the anaerobic microbial remediation in PCE or TCE-contaminated groundwater.


Asunto(s)
Chloroflexi , Dicloruros de Etileno , Tetracloroetileno , Tricloroetileno , Humanos , Anaerobiosis , ARN Ribosómico 16S/genética , Etilenos , Dicloroetilenos , Biodegradación Ambiental , Chloroflexi/genética
19.
Plant Cell Environ ; 47(6): 1941-1956, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38369767

RESUMEN

While soybean (Glycine max L.) provides the most important source of vegetable oil and protein, it is sensitive to salinity, which seriously endangers the yield and quality during soybean production. The application of Plant Growth-Promoting Rhizobacteria (PGPR) to improve salt tolerance for plant is currently gaining increasing attention. Streptomycetes are a major group of PGPR. However, to date, few streptomycetes has been successfully developed and applied to promote salt tolerance in soybean. Here, we discovered a novel PGPR strain, Streptomyces lasalocidi JCM 3373T, from 36 strains of streptomycetes via assays of their capacity to alleviate salt stress in soybean. Microscopic observation showed that S. lasalocidi JCM 3373T does not colonise soybean roots. Chemical analysis confirmed that S. lasalocidi JCM 3373T secretes indole-3-carboxaldehyde (ICA1d). Importantly, IAC1d inoculation alleviates salt stress in soybean and modulates its root architecture by regulating the expression of stress-responsive genes GmVSP, GmPHD2 and GmWRKY54 and root growth-related genes GmPIN1a, GmPIN2a, GmYUCCA5 and GmYUCCA6. Taken together, the novel PGPR strain, S. lasalocidi JCM 3373T, alleviates salt stress and improves root architecture in soybean by secreting ICA1d. Our findings provide novel clues for the development of new microbial inoculant and the improvement of crop productivity under salt stress.


Asunto(s)
Glycine max , Indoles , Raíces de Plantas , Estrés Salino , Streptomyces , Glycine max/fisiología , Glycine max/microbiología , Glycine max/crecimiento & desarrollo , Glycine max/efectos de los fármacos , Streptomyces/fisiología , Raíces de Plantas/fisiología , Raíces de Plantas/microbiología , Raíces de Plantas/metabolismo , Indoles/metabolismo , Tolerancia a la Sal , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos
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